Move copysign folds to match.pd

Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
OK to install?

Thanks,
Richard


gcc/
	* builtins.c (fold_builtin_copysign): Delete.
	(fold_builtin_2): Handle constant copysign arguments here.
	* match.pd: Add rules previously handled by fold_builtin_copysign.

On Mon, Oct 26, 2015 at 10:54 AM, Richard Sandiford
<richard.sandiford@arm.com> wrote:
> Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
> OK to install?

Ok.

Thanks,
Richard.

> Thanks,
> Richard
>
>
> gcc/
>         * builtins.c (fold_builtin_copysign): Delete.
>         (fold_builtin_2): Handle constant copysign arguments here.
>         * match.pd: Add rules previously handled by fold_builtin_copysign.
>
> diff --git a/gcc/builtins.c b/gcc/builtins.c
> index ae7e7ef..ed0030d 100644
> --- a/gcc/builtins.c
> +++ b/gcc/builtins.c
> @@ -7781,46 +7781,6 @@ fold_builtin_strncmp (location_t loc, tree arg1, tree arg2, tree len)
>    return NULL_TREE;
>  }
>
> -/* Fold function call to builtin copysign, copysignf or copysignl with
> -   arguments ARG1 and ARG2.  Return NULL_TREE if no simplification can
> -   be made.  */
> -
> -static tree
> -fold_builtin_copysign (location_t loc, tree arg1, tree arg2, tree type)
> -{
> -  if (!validate_arg (arg1, REAL_TYPE)
> -      || !validate_arg (arg2, REAL_TYPE))
> -    return NULL_TREE;
> -
> -  /* copysign(X,X) is X.  */
> -  if (operand_equal_p (arg1, arg2, 0))
> -    return fold_convert_loc (loc, type, arg1);
> -
> -  /* If ARG1 and ARG2 are compile-time constants, determine the result.  */
> -  if (TREE_CODE (arg1) == REAL_CST
> -      && TREE_CODE (arg2) == REAL_CST
> -      && !TREE_OVERFLOW (arg1)
> -      && !TREE_OVERFLOW (arg2))
> -    {
> -      REAL_VALUE_TYPE c1, c2;
> -
> -      c1 = TREE_REAL_CST (arg1);
> -      c2 = TREE_REAL_CST (arg2);
> -      /* c1.sign := c2.sign.  */
> -      real_copysign (&c1, &c2);
> -      return build_real (type, c1);
> -    }
> -
> -  /* copysign(X, Y) is fabs(X) when Y is always non-negative.
> -     Remember to evaluate Y for side-effects.  */
> -  if (tree_expr_nonnegative_p (arg2))
> -    return omit_one_operand_loc (loc, type,
> -                            fold_build1_loc (loc, ABS_EXPR, type, arg1),
> -                            arg2);
> -
> -  return NULL_TREE;
> -}
> -
>  /* Fold a call to builtin isascii with argument ARG.  */
>
>  static tree
> @@ -9278,7 +9238,16 @@ fold_builtin_2 (location_t loc, tree fndecl, tree arg0, tree arg1)
>        break;
>
>      CASE_FLT_FN (BUILT_IN_COPYSIGN):
> -      return fold_builtin_copysign (loc, arg0, arg1, type);
> +      if (TREE_CODE (arg0) == REAL_CST
> +         && TREE_CODE (arg1) == REAL_CST
> +         && !TREE_OVERFLOW (arg0)
> +         && !TREE_OVERFLOW (arg1))
> +       {
> +         REAL_VALUE_TYPE c1 = TREE_REAL_CST (arg0);
> +         real_copysign (&c1, TREE_REAL_CST_PTR (arg1));
> +         return build_real (type, c1);
> +       }
> +      break;
>
>      CASE_FLT_FN (BUILT_IN_FMIN):
>        return fold_builtin_fmin_fmax (loc, arg0, arg1, type, /*max=*/false);
> diff --git a/gcc/match.pd b/gcc/match.pd
> index e50f5bb..e02379f 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -2541,6 +2541,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
>   (POW real_onep@0 @1)
>   @0)
>
> +(simplify
> + /* copysign(x,x) -> x.  */
> + (COPYSIGN @0 @0)
> + @0)
> +
> +(simplify
> + /* copysign(x,y) -> fabs(x) if y is nonnegative.  */
> + (COPYSIGN @0 tree_expr_nonnegative_p@1)
> + (abs @0))
> +
>  /* Canonicalization of sequences of math builtins.  These rules represent
>     IL simplifications but are not necessarily optimizations.
>
>